If it's already brittle then sooner or later (sounds like sooner!) will crack or break. If lucky will only be a leak, if not a 3 1/2 hole in your deck
- and that could happen at an inconveniant time. If it's the only one like that left, sounds like the others went the same way and got replaced because they broke.
My advice is.......put it on the list (i.e. no need to rush with a replacement, but..........)
Anyway, welcome to CF.